Field
Exemplary embodiments relate to a light emitting diode (LED) module including a plurality of LEDs, and more particularly, to an LED module driven in response to alternating current (AC) power.
Discussion of the Background Art
As a part of low carbon green growth moving forward globally, a method of reducing illumination energy by introducing an LED lamp is being actively pushed forward.
Currently, LED lamps include a serial, parallel or serial-parallel combined group composed of a plurality of direct current (DC) LED devices, and are classified into DC drive type LED lamps, in which DC power is supplied to the LED devices through an internal or external power converter, and AC drive type LED lamps directly driven by AC power.
As shown in FIG. 1, a typical AC LED lamp includes two AC power terminals P1, P2 and a light emitting module 9. The AC power terminals P1, P2 are connected to the light emitting module 9 to directly supply AC power to the light emitting module 9.
The light emitting module 9 includes a first LED unit 91 and a second LED unit 92. Each of the first LED unit 91 and the second LED unit 92 includes at least one LED.
The first LED unit 91 and the second LED unit 92 are inversely connected to each other in parallel. Thus, the light emitting module 9 may be directly connected to an AC power source which allows the first LED unit 91 and the second LED unit 92 to alternately emit light along with AC power alternately repeating positive and negative voltage cycles.
There can be a slight deviation in color temperature of a plurality of LEDs produced from one wafer. This can be caused by various reasons such as deviation during a manufacturing process, for example, thickness deviation of a fluorescent layer coated onto an upper surface, and the like. However, since LEDs included in LED units are arranged in a typical AC LED lamp without consideration of deviation in color temperatures of the LEDs, there is a problem of difficulty in realization of a color temperature required for a final product.